SUNTONE ARCHITECTURE METHODOLOGY A 3-DIMENSIONAL ...

SUNTONE ARCHITECTURE METHODOLOGY
A 3-DIMENSIONAL APPROACH TO ARCHITECTURAL DESIGN
Key Concepts and Overview
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SUN MICROSYSTEMS . WHITE PAPER
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Contents
Executive Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
The Sun Approach for Dot-Comming . . . . . . . . . . . . . . . . . . . . . . . . .4
The Need for a Better Architectural Model . . . . . . . . . . . . . . . . . . . .4
The Limitations of Traditional Architecture . . . . . . . . . . . . . . . . . . .5
Services-Driven Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
The New Focus on “Network Services” . . . . . . . . . . . . . . . . . . . . . .6
Design Principles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
The Services-Driven Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
The 3–Dimensional Architectural Framework . . . . . . . . . . . . . . . . . .10
Systemic Qualities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Tiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Logical Application Tiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Physical Deployment Tiers . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Platform Layering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
3-Dimensional Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
The SunTone SM
Architecture Methodology . . . . . . . . . . . . . . . . . . . .21
Use Case-Focused . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Architecture-Centric . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Iterative and Incremental . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Systemic-Quality-Driven . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Patterns-Based . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Architecture at the Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
What is architecture? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Architectural Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
The Architectural Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Sun Microsystems, Inc.
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Architectural Views . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
Process, Patterns, and Views—The SunTone
Architecture Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Benefits Summary: 3D Architecture . . . . . . . . . . . . . . . . . . . . . . .34
How Sun Professional Services Can Help . . . . . . . . . . . . . . . . . . . . .35
Dot-Com-Ready Workshop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
Dot-Com Proof-of-Concept Services . . . . . . . . . . . . . . . . . . . . . . .35
Dot-Com Inception Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
Dot-Com Architecture Services . . . . . . . . . . . . . . . . . . . . . . . . . . .36
Sun’s Comprehensive Service and Support Capabilities . . . . . . . . . .37
About Sun Microsystems, Inc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
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SunTone Architecture Methodology

EXECUTIVE SUMMARY
The explosion of the web has fundamentally changed the mission and critical success
factors facing most corporate IT shops. The “users” are now real, live customers,
and there are tens of thousands or even millions of them. More than ever before, system
problems can result directly in lost revenue and lost customers. When a system
crashes and the phone rings, it’s not an angry branch manager on the phone—it’s CNN.
Until very recently, the vast majority of IT organizations developed applications
intended for deployment exclusively to their company’s employees. Although quality
has of course always been an important consideration in corporate software
development—nobody’s happy about a buggy release—a huge class of software defects
could be tolerated reasonably well by an enterprise. Periods in excess of months would
often roll by before glacial response times might be addressed through, for instance, a
massive mainframe upgrade. Employees would be given “workarounds” to deal with
various cases of software malfunction.
Corporate IT organizations are being faced with developing applications that are
more scalable, reliable, and secure than ever before, more quickly than ever before, and
with far greater Quality of Service (QoS) than ever before. IT organizations are
confronting huge challenges in retraining staff in Web-based technologies and
implementing the process changes necessary for rapid, successive, bug-free releases to
the web. Perhaps more than any other single factor, application architecture can make
or break a dot-com system. Get the architecture wrong, and a system can ultimately
prove impossible to scale, secure, or rapidly change.
Most of the biggest names on the Internet run on Sun, and many of their systems
have been built with the help of Sun Professional Services. Over the past several years,
Sun Professional Services has amassed a tremendous amount of expertise in building
dot-com applications. We have recently synthesized this learning into a standard process,
the SunTone SM
Architecture Methodology (SunTone AM).
This paper details the key concepts in a 3-dimensional approach to creating dot-com
system architecture. It gives an overview of:
• The 3-Dimensional Framework that analyzes an architecture in terms of the
three primary design dimensions: Application Tiers, Infrastructure Layers, and
Systemic Qualities.
Sun Microsystems, Inc.
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• The process of developing an architecture through the application of “architectural
patterns”.
• How QoS requirements should be used to drive the architecture definition process.
• How these principles are synthesized into the SunTone Architecture Methodology,
which is iterative and incremental, architecture-centric, use-case-focused, systemicqualities-driven,
and pattern-based.
THE SUN APPROACH FOR DOT-COMMING
Sun's comprehensive approach for dot-comming the enterprise consists of the following
primary components:
• SunTone SM
Architecture Methodology—a step-by-step process for creating dot-com
architectures.
• Our architecture reference model—a service driven architectural framework based
on loosely coupled, asynchronous communication.
• Architectural patterns—generic templates for structuring a system to meet rigorous
system level requirements like scalability, securability, and manageability.
• Solution sets—sample implementations of dot-com platforms such as e-tail, eCRM,
eSCM, or Community Portals.
• SI Partners—Consulting organizations certified to deliver the SunTone Architecture
Methodology and particular solution sets.
• ISV Partners—ISV products used to implement a solution set which are built with
Java2 Platform, Enterprise Edition (J2EE-technology) compliant products, or products
with a well-defined roadmap for migrating to J2EE.
This paper discusses the 3-Dimensional Architectural Model that is at the core of the
SunTone Architecture Methodology, and gives an overview of the methodology.
THE NEED FOR A BETTER ARCHITECTURAL MODEL
The dot-com age has fundamentally changed the rules of systems architecture. It has
changed end-user demands for IT services, management expectations for IT
infrastructure, and even the strategic role of the IT department. Legacy system
architectures were simply never envisioned to handle the number of users, the level of
security, and the pace of change required of dot-com systems.
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SunTone Architecture Methodology

Confronted with silo problems, many organizations adopt a strategy of Web-enabling
each silo independently. While achieving the short-term objective of making these
systems available over the Web, the resulting Web presence is fractured and difficult
for customers to navigate. More seriously, this approach makes it extremely difficult to
combine the functionality of various silos and create new value-added services.
Internet
Figure 2—Web Silos
For example, a company might separately Web-enable its order entry system and its
inventory system. Although this allows customers to check on product availability and
order products, it does not enable customers to check availability as part of the order
entry process, let alone suggest alternative products as substitutes for those that are
currently out of stock.
The systems architecture needs to support what might best be described as an enterprise
utility model. Like electricity through a power outlet or water through a faucet,
services need to be provided around the clock from standard access points to any
network device. These services need to bridge the silos to allow for an integrated,
customer-centric presentation of your business.
SERVICES-DRIVEN ARCHITECTURE
THE NEW FOCUS ON “NETWORK SERVICES”
The dot-com age is all about service delivery—anytime/anywhere access to any
needed service with predictable availability, reliability, performance, and security. The
SunTone Architecture Methodology focuses on how to identify, design, and deploy
network services to deliver this quality of service, within the severe time constraints
imposed by the dot-com space.
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Intranet
SunTone Architecture Methodology

SYSTEMIC QUALITIES
A new emphasis on Quality of Service (QoS) has emerged as Internet/E-commerce
services and applications have become larger and larger, and have become critical to
business operations. Achieving effective QoS requires integrating the development of
these capabilities into the design process of large-scale high-performance architectures.
This integration effort includes a process of specifying, designing and
implementing individual QoS, integrating the approaches for individual QoS into a
comprehensive strategy for monitoring and adapting the design for these capabilities
over time.
In many cases, such as availability, the phrase Quality of Service is synonymous with
the term “systemic qualities”, or what we might endearingly call the “ilities” (reliability,
availability, securability, reliability, etc.). However, some of the capabilities referred to,
such as flexibility, have not traditionally been included in discussions of QoS. We use
the term “systemic qualities” to apply to all of these system characteristics.
For the Internet, the focus of Quality of Service is different than the host-based and
client-server models of the past. For these new e-commerce systems the focus is on
real-time continuous processing for mission critical applications, not on a mainframe
model with programmed downtime and a batch-processing model. These new systems
are distributed heterogeneous environments that require a different perspective on
QoS. In some ways the challenge is more complex, on the other hand, if these architectures
are properly designed from the beginning, this can contribute to, and not
challenge, QoS achievement.
Specific examples of Systemic Qualities include:
• Performance—relates both to the specific performance metrics (e.g., responsiveness,
latency) and to the users’ expectations about performance.
• Reliability—related to the reliability of the underlying individual components in
servers. System reliability describes the likelihood of any component failures.
• Availability—essentially the percentage of time that the system is available for use.
Total availability is also impacted by factors beyond the architecture such as latency
within a user’s ISP or the general Internet.
• Scalability—Scalability relates to the ability of an e-commerce site to add capacity
and thus add users over time. Scalability will usually require the addition of
resources, but scalability should not require changes in the architecture, redesign or
loss of service due to the time required to scale.
• Security—includes the levels of authentication supported, the granularity of authorization
controls, the mechanisms for provided audibility and the techniques utilized
to ensure the integrity of resources, and the resistance to unauthorized access.
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SunTone Architecture Methodology

• Manageability—Manageability can be expressed in terms of how easy it is to monitor
a system and detect operational characteristics related to performance and failures,
how easy is to configure systems, the processes used for effecting this control
and the degree to which the system can be managed remotely.
• Accessibility—relates to the usability of applications across the full range of user
capabilities, languages, and devices.
• Flexibility—Flexibility relates to how easy is it to re-purpose the system to provide
different services. In flexible systems the individual components can be reorganized
to provide new services and used by different services.
• Other qualities—The list of capabilities is potentially inexhaustible. Other examples
include:
• Serviceability—how easy is it to repair the system and replace components, and to
what degree maintenance causes service interruption
• Interoperability—the capability of components to work with each other and the
ability to add new components
• Portability—the ability to move components from one environment to another or
replace platform components
• Reusability—the ability to use individual components or services in the building
of additional applications
• Usability—involves issues that make the user interface an application functionality
that is easy to use by the end user.
These Systemic Qualities are required at each tier of a dot-com architecture and are
not the responsibility of any given layer—instead the layers must complement and
cooperate in providing each quality within a given tier. Some qualities, such as security
or manageability, need to be pervasive—present at all layers in all tiers.
For this reason, the Sun 3-D Architectural Model represents these Systemic Qualities
as a separate dimension, orthogonal to the tiers and layers which represent the logical/distributed
partitioning and the platform layering. Viewing Systemic Qualities
(and the related QoS levels which need to be supported) in this way is one of the key
insights of the SunTone Architecture Methodology, and allows architectural
alternatives to be quantitatively and qualitatively evaluated for their ability to provide
these capabilities.
Sun Microsystems, Inc.
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To focus requirements gathering, guide integration of systemic qualities in design
and implementation, and drive ongoing management and improvement of QoS, it is
useful to categorize individual qualities in terms of the group that the quality impacts
most directly, the nature of the impact, and the time horizon within which the
qualities are manifested.
User-level qualities are those, such as usability and accessibility, that directly affect
the user interface and end-user functionality, are felt at run-time, and are controlled
in the design phase.
Service-level qualities are those, such as performance and availability, that directly
affect business functions of end-users, are felt at run time, and are controlled by
system management.
Strategic-level qualities are those, such as scalability and flexibility, that affect
the enterprise itself, are manifest over time, and are controlled primarily through
architecture. Of course, failures in scalability will result in failures in performance and
availability, which will be felt directly by the end user.
System-level qualities affect peripheral services and functions, such as manageability
and security, rather than business functionality. They are characteristics of the system
implementation, and often act as constraints to the implementation of other qualities
and are controlled by the operations staff.
Naturally, which category a particular quality falls in is relative to the business goals
and design of the systems. While security might be a system-level quality for most
applications, it may be a service-level quality for a company that is selling security
oriented services. The key to the use of these categories is not what category the
quality is in generally, but how each quality is experienced by what constituency and
how it is designed or controlled.
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SunTone Architecture Methodology

platforms have wrapped the “lower platform” thinly, without significantly raising the
level of abstraction. Today, virtual platforms are available that provide much more
comprehensive and high-level abstractions and directly support the model outlined in
this paper. The two leading virtual platforms for dot-com implementations are Java 2
Enterprise Edition (J2EE) and CORBA.
3-DIMENSIONAL EXAMPLE
Consider an extremely simplistic example in which a retail catalog firm wants to be
able to take orders over the Internet, initially via HTML forms from desktop browsers,
and from other device types in the future. A legacy order entry system is currently
used by their call center operators to enter customer orders received over the telephone,
and this system will be used as the back-end for a new web-based, customer
self-service system. A packaged solution is being considered as a replacement for the
legacy system. It has been determined that the best way to communicate with the
legacy system is via message queues.
The sample application platform architecture is depicted below.
Figure 6—Simple Order-Entry Example related to the 3DF
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Virtual
Upper
Lower
Hardware
HTML
Any Browser
Any OS
Any HW
CLIENT
JSP
iES
Solaris
E450
Order
Form
PRESENTATION
EJB
iAS
Solaris
E5500
Form
Handler
BUSINESS
JMS
MQ Series
Solaris
E250
Order
Service
INTEGRATION
Order
System
Interface
APPO
CICS
MVS
ES9000
RESOURCE
Legacy
Order
System
Parallelization
Queing
Clustering
Round Robin
Horizontal Scaling
Scaling Strategy
SunTone Architecture Methodology

The systemic qualities must be addressed within each tier, and at each layer. For this
example, we will first consider scalability. A horizontal scaling strategy is selected in
which requests will be distributed among multiple web servers, application servers,
and queues. Load will be distributed among the presentation tier web servers via
round-robin DNS. Native iPAS clustering will be used to distribute traffic among the
application servers. Each application server will be assigned its own MQ to avoid bottlenecks
in the integration tier. The choice to use queuing is itself a resource tier scalability
strategy since it allows the system to scale beyond the throughput capacity of
the Legacy Order System.
As an example of how layers need to cooperate within a tier to achieve a particular
systemic quality, consider a strategy that provides reliability by a “soft-clustering”
failover capability that is a feature of the iPlanet application server, in the upper
platform layer of the business tier. The architectural implications of this solution extend
into the application layer in that application components need to identify to their
platform which information is needed for failure recovery—full replication of all application
state would seriously degrade performance and increase resource usage. For this
capability to operate efficiently, the lower platform layers must provide high-speed interconnection
between application server instances to support replication of the failover
state. Tradeoffs between such a strategy for reliability and other strategies for scalability
(e.g. session affinity vs. request-dispatch load balancing) will need consideration as well.
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SunTone Architecture Methodology

THE SUNTONE SM
ARCHITECTURE METHODOLOGY
The SunTone AM builds on the ideas comprising the Unified Process. Like the Unified
Process, the SunTone AM is use-case-focused, architecture-centric, as well as iterative
and incremental. The SunTone AM significantly extends the Unified Process through
the incorporation of two additional fundamental concepts: it is systemic-qualities-driven,
and patterns-based. The SunTone AM refines the Unified Process notion of architectural
views to better reflect the extremely complex platform environments required for
dot-com applications.
USE CASE-FOCUSED
Use cases are functional scenarios that describe the complete flow of an operation
from the perspective of an actor. Actors are entities that are external to the system,
typically users or other systems. Examples of use cases are scenarios such as
“Customer browses on-line catalog”, or “Sales Representative enters order”.
In non-use-case-focused, strictly component-based approaches, components are
factored from an analysis and decomposition of the required functionality, and the
detailed design and development is typically performed within the context of creating
a complete component. A complete component, however, may not automatically be a
completely useful component, if its development was largely removed from the actual
context of end-to-end system functionality. An ongoing risk in developing components
is the production of extremely sophisticated components that include functionality
not required by the current application, or that ultimately do not integrate well with
the rest of the system.
In use-case-driven design and development, every attempt is made to prioritize
design and development around the realization of complete, end-to-end use cases. The
advantage of this approach is that it keeps the project team focused around continually
delivering functionality directly related to the end product being developed.
It helps avoid undue emphasis being placed on intermediate results at the expense of
end results, and provides a natural framework for an iterative, incremental process.
ARCHITECTURE-CENTRIC
In an architecture-centric approach, architecture is defined and validated before the
development teams begin the bulk of implementing the system design. This is
generally accomplished by building a prototype that exercises all of the unproven,
architecturally significant aspects of a system prior to the start of detailed design and
large-scale development. The architectural prototype focuses on such things as benchmarking
the performance of a volume of representative transactions, testing the
compatibility of various technologies, or certifying the smooth operation of a failure
recovery mechanism.
Sun Microsystems, Inc.
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Architecture Is Not about... Architecture Is about...
What happens when a button is pushed?
How the system should respond to an event.
Which bits of information should be supplied
in response to an event.
What are the business rules?
What is the database schema?
What are the fields of the messages?
A system’s design is constrained by its architecture. In other words, the system
architect establishes the “big rules” that must be followed by the system designers
(who in turn determine how the desired functionality should be realized by the
system implementers). The process of architecture ends and the process of design
begins when enough big rules have been established to ensure that as long as a design
complies with the big rules, it will satisfy the system’s service level requirements.
Sun Microsystems, Inc.
How often the button is pushed, how many
users are simultaneously pushing the button,
where the users physically are (e.g. inside the
intranet, out on the Internet, etc.) when they
push the button.
The timing constraints, if any, between events.
What kinds of constraints should be placed
on which kind of data, based on which user
characteristics.
How complex are the rules? How often are
they changed? Can they be changed by
programmers or by users themselves? Will
they be implemented by a single individual,
or by separate teams? Do they change
together or independently?
How complex is the schema, are there any
pre-existing constraints around it? (E.g. predefined
DB.)
What are the external systems that could be
or must be interacted with, and what are
their characteristics?
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Figure 8—Architecture constrains Design
Architectural Patterns
In defining an architecture, the system architect considers and applies structuring
principles that satisfy some set of service level requirements. These structuring
principles often take the form of recognized design patterns, which can be applied to
meet specific service level requirements. For example, various load distribution patterns,
such as round robin, least-loaded-, or session-affinity-dispatch, can be used
to meet scalability requirements. As another example, replication patterns such as
mirroring, store-and-forward, or 2-phase commit can be used to achieve high-availability.
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Tiers Tiers
Unconstrained Tiered Tiered and Layered
Layers
SunTone Architecture Methodology

REQUEST
DISPATCHER
LOAD BALANCING
Figure 9—Architectural Pattern Examples
TRANSACTION
TRANSACTION
MIRRORED
RESOURCES
REPLICATION
Many design patterns are applicable within each of several layers of the implementation
stack. Replication, for example, can be applied at the application layer, via 2-phase
commit logic, in the upper platform, via native database replication, or at the hardware
layer, via RAID.
Sun Microsystems, Inc.
REQUEST
HANDLERS
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Figure 10—Patterns by Layer
Similarly, many design patterns are applicable within or across multiple tiers. Load
distribution, for example, can be applied in the Presentation Tier, via dispatching
requests to one of several web servers, in the Business Tier, by dispatching a request to
one of several application servers, and in the resources Tier, by dispatching to one of
several database segments.
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Application
2 phase commit
• Fine granularity
• Highest reliability
• Holds under failure
• Program each app
Messaging • Fine granularity
• User independent
• N-way
Database
replication
• Table level
• Applies field validation
Disk level copy • Coarse granularity
• Replicates corruption
SunTone Architecture Methodology

Figure 11—Patterns by Tier
The Architectural Process
The architecture definition process consists largely of the selection of design
patterns and their application to various structural elements of a system in order to
meet a set of service level requirements. The process begins with the selection of an
initial broad pattern, referred to as the Architectural Style. The selection of this initial
pattern is based on previous experience or simple heuristics applied with respect to
the type of application to be developed. The 3-Dimensional Framework discussed
earlier in this paper, with its tiers and layers, is an example of an architectural style
with fairly universal applicability to “dot-com applications”, i.e., applications with a
huge number of users, accessible by a variety of channels over a public network.
Once an architectural style has been selected, it is useful to make initial assumptions
about how the layers and tiers should be provisioned with system components
and services. These assumptions are typically based on experience-based implementation
preferences for things like technologies and programming models, and a highlevel
consideration of the Systemic Quality requirements. For example, an
organization that has standardized on the J2EE technology platform model would
likely make an initial assumption that J2EE would be included within the Virtual
Platform. Similarly, if the project developers have experience with a specific EJB technology-based
server implementation, it would make sense to initially assume the presence
of that EJB Server in the Upper Platform.
Sun Microsystems, Inc.
• Client application
— Built-in retry
• Internet Cloud
— Cisco Global Director
• Switching Fabric
— Alteon
• Web Front End
— Resonate Dispatch
• Application Server
— iPlanet server
• Messaging
— Tuxedo Messaging
• Database Resiliency
— Oracle SQLNet redirection
• Server Infrastructure
— SunCluster
29

Several views, distinguished largely by the perspective of several stakeholders, are
often required to specify all facets of an architecture depending on its complexity.
Each view serves a different set of stakeholders with different concerns, interests, and
technical capabilities. Collectively the views represent the primary content of the
System Architecture Document.
The definitions of layers in the 3–Dimensional Framework, and the interfaces
between them, have co-evolved in modern computing culture with a set of disciplines
that manage the complexity within each layer. Thus an IT organization may have
different groups which focus on providing and managing platforms at the hardware,
network, OS, upper-platform, and application layers—indeed, some of these layers may
be outsourced entirely.
For this reason, the layers frequently provide a useful framework for views that
address the needs of different groups of stakeholders among those responsible for
creating, deploying, managing, and evolving the system. The SunTone AM categorizes
its views by layers. Layers reflect the primary distinguishing factor among skill sets
within and across the development team. Additionally, layers reflect different opportunities
to incorporate components and COTS from multiple sources. Within each
layer, views can describe different aspects of the architecture such as:
• Software and hardware configurations of architecturally significant components at
different levels of detail
• Descriptions of representative dynamic interactions fulfilling targeted functionality
or systemic qualities
• Incorporated and custom mechanisms such as persistence, inter-process communication,
and transaction management
• Evolutionary considerations
Within views, various types of models are used to effectively communicate structure
and purpose. This includes the use of the Unified Modeling Language (UML) and
extensions, as well as summarizations that help to ensure that systemic qualities are
being focused on at all levels. For example, a matrix format can highlight the approach
to systemic qualities across different layers. In this format, the rows represent the system
layers, and the columns represent the systemic qualities relevant to this system.
Each cell describes a feature, strategy, product, practice, or some combination thereof
employed at that layer to support the specified systemic quality:
Sun Microsystems, Inc.
31

Layers
Upper Platform
Vitrual Platform
Application
The system is also driven from a Domain Object Model (DOM), which is not a view
per se, but a starting point for system development. The domain object model is a logical
object model of the problem domain, identifying the business entities and their
relationships. Along with general business rules, it captures constraints and invariants
of the underlying problem domain. The model should refer only to the business entities
and activities, not to solution-domain mechanisms. Somewhat of an art, an effective
domain model can significantly and favorably impact schedules and design
decisions by minimizing design efforts going down the wrong paths.
Defining this model may begin early in inception by defining essential entities.
Further definition will continue through elaboration. A well-specified domain object
model enhances the functional specification, and provides an ongoing source of documentation
for later project participants.
Process, Patterns, and Views—the SunTone Architecture Methodology
The architectural core of the SunTone AM consists of iteratively defining each of the
various architectural views. The process begins with identifying the various tiers that
will make up the application, and then defining each view by considering the required
System Qualities, and applying component patterns accordingly. At each step in the
process, the architect determines whether an as yet un-addressed System Quality will
be addressed directly within the current view, or whether to defer the implementation
of that quality to a lower layer in the stack.
32
Components Security Reliability Scalability Availability Managability Performance Portability
Server
Redundant
system
components
SNMP on H/W tuned CPU/
components memory/IO
Hardware Sun E5500 lockdown
Add Servers N+1 Servers Remote Admin configuration
SNMP,
Remote
Solaris,
Redundant Admin Solaris
iPDS, Firewalls
Network Resource
Lower Platform Firewall SSL
Connections Manager Instance Tuning
iPAS 60
EJBs and
CMP
LDAP
based
uid/pw
J2EE
Security
Model
Order Service uid/pw
iPAS softcluster
failover
identified
failover
state
Multiple
instances,
thread/
sessions pools
N+1
instances
iPAS mgnt.
console
JDMK
JDMK
session affinity
load balancing
Solaris
Production JVM
good code
Any
Enterprise
Server
Any Solaris
Platform
Solaris, NT
Any J2EE
platform
SunTone Architecture Methodology

HT HTML ML
An Any
Br Browser wser
Any OS
OS
An Any y HW
HW
CLIENT
JSP
AP APACHE CHE
SOLARIS
E450
EJB
IAS
SOLARIS
E5500
Figure 13—Systemic-Quality-driven Patterns iteratively applied to an Architecture
As illustrated in Figure 13, the patterns are applied across tiers and layers, and their
selections are driven by the Systemic Qualities.
An important component of the SunTone AM is our Patterns Catalog, which details
architectural patterns and provides guidance as to how each should be used.
This approach unites the Sun 3-D Framework as an architectural style; an iterative,
pattern-driven architectural process; and view-based architectural expression into a
single whole. By bringing together Sun’s long experience in dot-com architecture, the
proven and respected Unified Process, and the best current practices in pattern-based
systems, the SunTone AM provides an invaluable guide for the working system
architect in the dot-com age.
Sun Microsystems, Inc.
CUSTOMER
PRESENTATION
SEGMENT
BUSINESS
JMS
MQ SERIES
SOLARIS
E250
ORDER
PRODUCT
INTEGRATION
APPC
CICS CIC CICS
MVS MV
ES9000
LINE ITEM
RESOURCE
PATTERNS
•PARTITIONING
•DISTRIBUTION
•ACCESS CONTROL
•LOAD BALANCING
•FAILOVER
CATALOG
33

BENEFITS SUMMARY: 3D ARCHITECTURE
The dot-com age is upon us because of a simple technology fact—we are in an age of
ubiquitous, inexpensive, everyone-to-everyone connectivity. As former islands of technology
connect, they cease to become systems unto themselves and instead become
part of a huge, globally-connected, loosely-coupled, massively distributed super-system.
In this context, the demands for scalability, availability, security, and robustness
are of a completely different order than they have been in the island days. Leveraging
this ubiquitous connectivity and the global super-system has become a key source of
competitive advantage—and so flexibility, adaptability, and extensibility for dot-com
architectures have become mission-critical, strategic requirements.
These factors combine to demand a new architectural approach, which identifies the
qualities a system or infrastructure needs to deliver value to the business which is
building it, and uses these qualities as its driving principles. When done properly, the
result is an architecture that delivers value beyond its simple functions, now and into
the future.
The 3-Dimensional Framework, SunTone AM, and Patterns provide a clear, compelling
approach that fills this need. It does not make dot-com architecture into a simple cookbook,
but it does provide a frame of reference in which a talented, experienced architect
can make the right decisions quickly and with confidence. The result:
• Systems with the scalability, reliability, and security demanded in the dot-com age:
Whether it’s “Anyone, Anywhere, Anytime, on Anything” or “Everyone, Everywhere, All
the time, on Everything”, dot-com architectures need to drive from the qualities they
will have to deliver. By framing the systemic qualities of the system as strategic
requirements and relating them properly to the logical and implementation
dimensions, the 3-Dimensional Framework allows an architecture to be described
and analyzed at design time for its delivery of these capabilities.
• Flexible systems and real reuse: A system delivered in a browser today may need to be
delivered to a hand-held device, an automobile, or a programmatic agent in the near
future. By enforcing the separation of concerns implicit in the tiered approach, and by
analyzing the functionality in terms of business services, the 3-Dimensional
Framework allows presentation, business, and resource implementations to evolve
independently. By designing and deploying functionality as network-available services
with extremely high QoS, the framework encourages real reuse of these services without
the cost of code ownership and deployment for each project.
• Systems with a long lifespan and the ability to evolve: The promise of standards-based
computing, embodied in the 3-D framework’s virtual platform layer, helps ensure that
architects and developers can spend more time addressing business issues rather
than technical issues. It allows for platform independence, allowing your enterprise to
take advantage of advances in computing hardware, network technologies, and
software without expensive reengineering of core dot-com applications.
34
SunTone Architecture Methodology

HOW SUN PROFESSIONAL SERVICES CAN HELP
Sun Professional Services has created an array of dot-com consulting services that
address all aspects of SunTone Architecture Methodology: architecture analysis, design,
and deployment. The services range from the Dot-Com Architecture Service to development
and deployment services such as the Dot-Com Inception service. Wherever you
are on your road to building a 3Dimensional architecture, Sun Professional Services can
help you take the next step quickly, correctly, and cost-efficiently.
DOT-COM-READY WORKSHOP
Sun’s Dot-Com-Ready Workshop is a good first step for defining your dot-com business
strategy and evaluating the technical requirements of building a 3–dimensional
Architecture. The workshop is customizable for your specific needs and will show you
how Sun consulting services, architectural approaches, competency center offerings,
and specific products and services can help you build your 3–Dimensional Architecture.
DOT-COM PROOF-OF-CONCEPT SERVICES
These services provide a concrete validation of your dot-com strategy. Our project
team helps your technical staff and ISVs jumpstart your dot-com project, and our
iForce SM
ready centers provide a unique environment to develop, test, and evaluate your
dot-com solutions. The project team examines your IT infrastructure as a set of logical
and physical components, then builds a customized, demonstrable proof-of-concept of
the technology supporting your business needs.
DOT-COM INCEPTION SERVICE
Sun’s consultants work closely with your team to explore and identify key Internet
and Java technologies that can advance your critical success factors. We’ll assess your
current IT environment and map out the technology you’ll need to deliver on the service-level
commitments you’ve made or want to make. We’ll advise you about technical
aspects of Internet business strategy, identify key technical goals, scope, and
success factors, help you align your architecture strategy with your business goals,
design and document the high-level technical requirements of the architecture, and
collaborate with your staff and Web design consultants to identify use cases, develop
the user interface prototype, and document the content architecture.
Sun Microsystems, Inc.
35

DOT-COM ARCHITECTURE SERVICES
Sun consultants can help you architect a versatile foundation that will reliably
support the anticipated growth of your business and the rapid deployment of new
network services. Dot-Com Architecture Services help you put in place an architecture
based on the multi-tiered, services-driven methodology that is described in this paper.
Sun consultants also help you put in place the policies and procedures that enable you
to limit your network security exposures. Specific activities include:
• Develop an architectural prototype that demonstrates and validates the solution
• Develop a master architectural plan that outlines the entire architecture, the relation
of the architecture to the strategic requirements, and the identification of the
COTS components and any necessary custom application development
• Provide a project architecture plan and a phased project plan
• Design the software solution and infrastructure architecture
36
SunTone Architecture Methodology

SUN’S COMPREHENSIVE SERVICE AND SUPPORT CAPABILITIES
As a global corporation and a market leader in UNIX® servers, system software, storage
systems, and workstations, Sun understands the importance of comprehensive,
end-to-end service and support. Our services for the enterprise include:
• Support Services: Sun’s support services offer the proactive systems support, the
expert knowledge transfer, and the seamless service integration you need to help
meet your mission-critical uptime objectives. Our systems support programs focus
on proactive failure prevention, rapid recovery, and technical services planning for a
global corporation’s enterprise network environments.
• Professional Services: Sun Professional Services can help you create or restructure
your IT infrastructure to leverage the Internet for optimal performance and service
quality. Sun consultants provide a full spectrum of IT planning and integration consulting
services, systems and network management services, Internet/intranet planning
and integration services, and dot-com consulting services.
• Educational Services: Sun is an industry leader in technical education, providing
expert training, education consulting, and certification services. Sun can help
ensure that your staff has the right skills at the right time to deploy and manage
your enterprise networking technology. We can provide a wide range of education
and migration services—through a broad array of delivery options—to help you
maximize your investment in technology.
ABOUT SUN MICROSYSTEMS, INC.
Since its inception in 1982, a singular vision, “The Network Is The Computer” has
propelled Sun Microsystems, Inc. to its position as a leading provider of industrialstrength
hardware, software, and services that power the Internet and allow companies
worldwide to dot-com their business. With more than $17.6 billion in annual
revenues, Sun can be found in more than 150 countries and on the World Wide Web at
http://sun.com.
Sun Microsystems, Inc.
37

HEADQUARTERS SUN MICROSYSTEMS, INC., 901 SAN ANTONIO ROAD,PALO ALTO, CA 94303-4900 USA
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© 2001 Sun Microsystems, Inc. All rights reserved. Sun, Sun Microsystems, the Sun logo, Java, Enterprise JavaBean, JavaServer Pages, Solaris, SunReady, Java 2 Platform, Enterprise Edition, iPlanet, Sun Cluster, SunTone
Architecture Methodology, and iForce are trademarks, registered trademarks, servicemarks or registered servicemarks of Sun Microsystems, Inc. in the United States and other countries. Products bearing SPARC
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